Abstract: A high-resolution radioisotopic imaging system employs spaced-apart non-contiguous thin and thick electronic collimation detectors arranged about a radioisotopic source field of radioisotopic atoms, each operative for detecting a plurality of gamma rays, or at least one position, or a combination of at least one position and at least one gamma ray. The detectors specify a plurality of emission probability fields which intersect in space to form a reduced emission probability field.

Abstract: This invention relates to the use of differential separative properties and modified assay containers in improving the convenience of separative scintillation proximity assay (SSPA) and extending its range of practical application.

Abstract: A concept and various means of immunological assay are disclosed wherein two different classes of particles which interact at short distances to produce characteristic detectable signals are employed in a modification of the usual latex fixation test. In one embodiment of the concept an aqueous suspension of appropriately coated tritiated latex particles (LH) and polystyrene scintillant particles (L*) is employed. The amount of (LH) (L*) dimer formation and higher order aggregation induced and therefore the concentration of antibody (or antigen) present which caused the aggregation can be determined by using standard liquid scintillation counting equipment. Also, an optical container for use in the assay which has one side provided with a section forming a quadrilateral prism with the prism providing for an angle of incidence greater than the critical angle for an electromagnetic beam of radiation.

Abstract: This invention relates to improved energy-emitting latex-particulates for use in a non-destructive method of biological assay, wherein the biological material under assay links the distinct and different particulates in such a manner that their proximity results in a detectable signal which is indicative of the amount of such biological material present in the fluid.More particularly, this invention relates to improved energy-emitting latex-particulates which have improved stability, a greatly extended shelf-life, particularly in the fluid suspension state, and whose use in the quantitative assay of immunological material results in a reduced background signal and improved sensitivity and stability.

Abstract: An indirect, non-destructive, quantitative assay for the presence of antigens or antibodies in a biological fluid. The assay is based on the interfunctional behavior of a known biological material with the material whose presence is quantitatively sought. In the assay, the known biological material by a correlative action links two discreet interfunctional particles together within a zone of activation with one of the particles emitting light-pulses upon bombardment of electrons from the other particle within the zone of activation. Depending upon which presence is sought to be measured, i.e.; antigen or antibody, the detectable light-pulses give one measurement which gives the ultimate quantitative measurement of the presence of either an antibody or antigen in the biological fluid after their initial interfunctional behavior one to the other. The interfunctional behavior itself is conventional and known in the art.

Abstract: A concept and various means of immunological assay are disclosed wherein two different classes of particles which interact at short distances to produce characteristic detectable signals are employed in a modification of the usual latex fixation test. In one embodiment of the concept an aqueous suspension of appropriately coated tritiated latex particles (LH) and polystyrene scintillant particles (L*) is employed. The amount of (LH) (L*) dimer formation and higher order aggregation induced and therefore the concentration of antibody (or antigen) present which caused the aggregation can be determined by using standard liquid scintillation counting equipment.